The role of exchangeable cations in preservation of soil fertility

U radu je analiziran utjecaj kationa adsorpcijskog kompleksa na plodnost tala. Na području Slavonije i Baranje odabrano je 20 lokacija za 4 tipa tla (pseudoglej, luvisol, černozem i solonec). Uzorci iz oraničnih i podoraničnih slojeva prikupljeni su na terenu, a nakon laboratorijskih analiza određen je tip tla. Rezultati analiza pokazuju ekstremno do jako kiselu reakciju u pseudoglejima i luvisolima (pH-KCl 3,85 – 5,18; pHH2O 5,45 – 6,50), a u černozemima i solonecima slabo kiselu do vrlo jako alkalnu (pH-KCl 6,00 – 8,80; pHH2O 7,08 – 10,21). Veličina KIK-a ovisi o količini i tipu minerala gline i sadržaju organske tvari. Najniže vrijednosti su zabilježene u pseudoglejima i luvisolima (11,46 – 22,07 cmol(+) kg-1), a najviše u černozemima (27,75 – 121,20 cmol(+) kg-1). U tlima kisele reakcije koncentracija Ca2+ je niska, a udio H+ iona je 19,73 - 56,29 %. Uz Hk > cmol(+) kg-1 potrebno je provesti kalcizaciju i rahljenje zbijenih podoraničnih slojeva pseudogleja. U sastavu AK soloneca koncentracija Ca2+ je ispod optimalne. Međutim, pH upućuje na visoke koncentracije Mg2+ (32,94 – 72,41 %) i Na+ (0,32 – 37,55 %). Plodnost ovih tala je vrlo niska, jer uslijed alkalizacije se pogoršavaju fizikalno-mehanička svojstva (struktura, konzistencija, čvrstoća). Obvezno je provesti mjere popravke unošenjem gipsa, snižavanjem razine podzemne vode i drenažom.The paper analyzes the influence of cation exchange complex on soil fertility. In the Slavonia and Baranja region, a sample of 4 types of soil (Stagnosols, Luvisols, Chernozems and Solonetz) at 20 different locations was selected. Samples from arable and subarable submarine layers were collected on the field, and after the laboratory analyzes the soil type was determined. The results of the analyzes show extreme to very acidic reaction in Stagnosols and Luvisols (pH-KCl 3.85-5.18, pH-H2O 5.45-6.50). Poorly acidic to very alkaline reaction (pH-KCl 6.00 - 8.80, pH-H2O 7.08 - 10.21) occurred in Chernozems and Solonetz. The size of KIK depends on the amount and the type of clay mineral and the content of organic matter. The lowest values were recorded in Stagnosol and Luvisols (11.46 - 22.07 cmol(+) kg- 1), and the highest in Chernozem (27.75 - 121.20 cmol(+) kg - 1). In acidic soils the Ca2 + concentration is low and the H+ ion content is 19.73-56.29%. With Hk > cmol(+) kg-1 it is necessary to carry out the calcification and rupture of compressed underwater layers of Stagnosols. The Ca2 + in Solonetz is below optimum. However, the pH indicates high concentrations of Mg2+ (32.94-72.41%) and Na+ (0.32-37.55%). The fertility of these soils is very low, as the alkaline phenomena are aggravated by physical and mechanical properties (structure, consistency, strength). It is imperative to carry out repairs by placing plaster, lowering the groundwater level and draining